DSNB507I VDWQT FOR `bpname` MUST BE BETWEEN 0 AND 90

Explanation
An attempt was made to change a buffer pool's VDWQT attribute to an invalid
value using the ALTER BUFFERPOOL command. VDWQT is the vertical deferred write
threshold. Valid values range from 0 to 90.

System action
The request is rejected.

System programmer response
Reissue the ALTER BUFFERPOOL command, specifying a legitimate VDWQT value.